Elsevier

Injury

Volume 46, Issue 6, June 2015, Pages 1119-1126
Injury

A prospective randomised study comparing TightRope and syndesmotic screw fixation for accuracy and maintenance of syndesmotic reduction assessed with bilateral computed tomography

https://doi.org/10.1016/j.injury.2015.02.004Get rights and content

Abstract

Background

The accuracy and maintenance of syndesmosis reduction are essential when treating ankle fractures with accompanying syndesmosis injuries. The primary aim of this study was to compare syndesmosis screw and TightRope fixation in terms of accuracy and maintenance of syndesmosis reduction using bilateral computed tomography (CT).

Study design

Single centre, prospective randomised controlled clinical trial; Level of evidence 1.

Methods

This study (ClinicalTrials.gov, NCT01742650) compared fixation with TightRope® (Arthrex, Naples, FL, USA) or with one 3.5-mm tricortical trans-syndesmotic screw in terms of accuracy and maintenance of syndesmosis reduction in Lauge-Hansen pronation external rotation, Weber C-type ankle fractures with associated syndesmosis injury. Twenty-one patients were randomised to TightRope fixation and 22 to syndesmotic screw fixation. Syndesmosis reduction was assessed using bilateral CT intraoperatively or postoperatively, and also at least 2 years after surgery. Functional outcomes and quality of life were assessed using the Olerud–Molander score, a 100-mm Visual Analogue Scale, the Foot and Ankle Outcome Score, and the RAND 36-Item Health Survey. Grade of osteoarthritis was qualified with follow-up cone-beam CT.

Results

According to surgeons’ assessment from intraoperative CT, screw fixation resulted in syndesmosis malreduction in one case whereas seven syndesmosis were considered malreduced when TightRope was used. However, open exploration and postoperative CT of these seven cases revealed that syndesmosis was well reduced if the ankle was supported at 90˚. Retrospective analysis of the intra- and post-operative CT by a radiologist showed that one patient in each group had incongruent syndesmosis. Follow-up CT identified three patients with malreduced syndesmosis in the syndesmotic screw fixation group, whereas malreduction was seen in one patient in the TightRope group (P = 0.33). Functional scores and the incidence of osteoarthritis showed no significant difference between groups.

Conclusion

Syndesmotic screw and TightRope had similar postoperative malreduction rates. However, intraoperative CT scanning of ankles with TightRope fixation was misleading due to dynamic nature of the fixation. After at least 2 years of follow-up, malreduction rates may slightly increase when using trans-syndesmotic screw fixation, but reduction was well maintained when fixed with TightRope. Neither the incidence of ankle joint osteoarthritis nor functional outcome significantly differed between the fixation methods.

Introduction

The classic presentation of syndesmotic disruption occurs in addition to Lauge-Hansen pronation-external rotation (PER) Danis-Weber type C ankle fracture [1], [2]. Malreduction of the syndesmosis that alters tibiofibular joint kinematics is reported to impair ankle function and lead to early osteoarthritis [3], [4], [5]. Therefore, accuracy and maintenance of reduction of the syndesmosis are considered essential when treating ankle fractures with concomitant syndesmosis injury [4], [6], [7], [8], [9].

Metallic trans-syndesmotic screw has been the most popular fixation method to stabilise unstable syndesmosis [10], [11], [12]. However, syndesmosis malreduction is reported to occur up to more than 50% in syndesmotic screw fixation [13], [14], [15], [16], [17], [18]. A further problem with syndesmosis screws is the potential late diastasis due to screw breakage or screw removal [13], [17], [19], [20].

Flexible TightRope® (Arthrex, Naples, FL, USA) suture-button device was developed for physiologic stabilisation of the ankle mortise; its use has increased rapidly over the last years [21]. Theoretically, this suture-button device allows physiologic motion of the syndesmosis without need for implant removal, which may lower the risk of recurrent syndesmotic diastasis as described after syndesmosis screw removal [11]. Biomechanical investigations have demonstrated that the strength of TightRope device is comparable to a tricortical 3.5 mm syndesmotic screw [22], [23], [24]. Several recent studies assessed syndesmosis stabilisation with suture-button device [25], [26], [27], [28], [29] and comparative studies reported at least as good functional results with this device in comparison to syndesmotic screw [18], [30], [31], [32], [33]. Previously the rate of syndesmosis malreduction associated with suture-button device ranged from 0% to 11% [18], [25], [29], [30], [33], [34].

The majority of earlier studies of syndesmosis fixation used only plain radiographs to assess syndesmosis reduction [8], [13], [25], [26], [29], [30], [35], [36], [37], [38]. Intra-operative fluoroscopy and post-operative conventional radiography are currently considered inaccurate to assess syndesmosis reduction; [14], [17], [18], [39] computer tomography (CT) of both ankles is recommended [17], [18], [40], [41], [42], [43], [44], [45].

Only a few published clinical studies with functional results have assessed syndesmotic reduction with bilateral CT, [16], [17], [18] and none of them has used both intra-operative and follow-up CT for assessing syndesmosis reduction. Furthermore, only two prospective randomised controlled trial has compared screw and TightRope for syndesmosis fixation [32], [33].

The primary purpose of this prospective randomised trial comparing fixation via syndesmosis screw or TightRope was to assess the accuracy and the maintenance of syndesmosis reduction using bilateral CT. The secondary purpose was to compare functional outcome and the rate of OA after at least 2 years of follow-up. Based on previous literature, we hypothesised that the malreduction rate of screw fixation would be 50%, and the malreduction rate of TightRope fixation would be 5%.

Section snippets

Study design

We conducted a prospective randomised trial (ClinicalTrials.gov, NCT01742650) comparing fixation via TightRope® or via one 3.5-mm tricortical trans-syndesmotic screw for the treatment of syndesmosis injury in Lauge-Hansen pronation-external rotation-type ankle fractures. CONSORT-guidelines were followed (http://www.consort-statement.org). The ethical committee of our hospital approved the study protocol.

Study population

All skeletally mature patients (16 years or older) who visited emergency department of an

Results

Baseline characteristics of the patients are shown in Table 1.

Discussion

The present prospective randomised trial showed that syndesmotic screw and TightRope fixation resulted in a low malreduction rate (5%) and both methods maintained reduction well (syndesmotic screw 84% and TightRope 95%). However, intraoperative CT scanning was unreliable when assessing TightRope fixation, and false positive findings were common. Therefore, the value of intraoperative CT scanning may be questioned and open exploration may be a better technique than CT to confirm syndesmosis

Conclusion

Syndesmotic screw and TightRope fixation had similar postoperative malreduction rates in patients with pronation-external rotation, Weber C-type ankle fracture and associated syndesmosis injury. Intraoperative CT scanning of the ankles with TightRope fixation can be misleading due to dynamic nature of the fixation, unless scanning technique is meticulous with the ankle supported in 90 degrees’ angle. After at least 2 years of follow-up, analysis of bilateral CBCT data suggested that the rate of

Funding

The study was supported by Oulu University Central Hospital. The funding source had no influence or involvement in the study.

Conflict of interest

Medical Physicist, PhD Jani Katisko has a consultant service agreement with Medtronic Finland Oy. All other authors declare that they have no financial or personal relationships that could influence this study.

References (61)

  • H.C. Leeds et al.

    Instability of the distal tibiofibular syndesmosis after bimalleolar and trimalleolar ankle fractures

    J Bone Joint Surg Am

    (1984)
  • U. Lindsjo

    Operative treatment of ankle fracture-dislocations. A follow-up study of 306/321 consecutive cases

    Clin Orthop Relat Res

    (1985)
  • P.L. Ramsey et al.

    Changes in tibiotalar area of contact caused by lateral talar shift

    J Bone Joint Surg Am

    (1976)
  • S.D. Boden et al.

    Mechanical considerations for the syndesmosis screw. A cadaver study

    J Bone Joint Surg Am

    (1989)
  • H.R. Chissell et al.

    The influence of a diastasis screw on the outcome of Weber type-C ankle fractures

    J Bone Joint Surg Br

    (1995)
  • J.S. Xenos et al.

    The tibiofibular syndesmosis. Evaluation of the ligamentous structures, methods of fixation, and radiographic assessment

    J Bone Joint Surg Am

    (1995)
  • M.P. van den Bekerom et al.

    Current concepts review: operative techniques for stabilizing the distal tibiofibular syndesmosis

    Foot Ankle Int

    (2007)
  • T. Schepers

    Acute distal tibiofibular syndesmosis injury: a systematic review of suture-button versus syndesmotic screw repair

    Int Orthop

    (2012)
  • T.J. Van Heest et al.

    Injuries to the ankle syndesmosis

    J Bone Joint Surg Am

    (2014)
  • B. Weening et al.

    Predictors of functional outcome following transsyndesmotic screw fixation of ankle fractures

    J Orthop Trauma

    (2005)
  • M.J. Gardner et al.

    Malreduction of the tibiofibular syndesmosis in ankle fractures

    Foot Ankle Int

    (2006)
  • A.N. Miller et al.

    Direct visualization for syndesmotic stabilization of ankle fractures

    Foot Ankle Int

    (2009)
  • A.K. Wikeroy et al.

    No difference in functional and radiographic results 8.4 years after quadricortical compared with tricortical syndesmosis fixation in ankle fractures

    J Orthop Trauma

    (2010)
  • H.C. Sagi et al.

    The functional consequence of syndesmotic joint malreduction at a minimum 2-year follow-up

    J Orthop Trauma

    (2012)
  • G.A. Naqvi et al.

    Fixation of ankle syndesmotic injuries: comparison of TightRope fixation and syndesmotic screw fixation for accuracy of syndesmotic reduction

    Am J Sports Med

    (2012)
  • A.N. Miller et al.

    Functional outcomes after syndesmotic screw fixation and removal

    J Orthop Trauma

    (2010)
  • Y.T. Hsu et al.

    Surgical treatment of syndesmotic diastasis: emphasis on effect of syndesmotic screw on ankle function

    Int Orthop

    (2011)
  • E. Bava et al.

    Ankle fracture syndesmosis fixation and management: the current practice of orthopedic surgeons

    Am J Orthop (Belle Mead NJ)

    (2010)
  • S.P. Soin et al.

    Suture-button versus screw fixation in a syndesmosis rupture model: a biomechanical comparison

    Foot Ankle Int

    (2009)
  • R. Klitzman et al.

    Suture-button versus screw fixation of the syndesmosis: a biomechanical analysis

    Foot Ankle Int

    (2010)
  • Cited by (134)

    • What is the best treatment for syndesmosis fixation? Suture-button or syndesmotic screw ? Bilateral CT-based early postoperative analysis

      2023, Foot and Ankle Surgery
      Citation Excerpt :

      However, 3D systems may not be available in every clinic and it can be difficult and time-consuming to evaluate these images. In a study by Kortekangas et al., syndesmosis reduction was evaluated on bilateral intraoperative and postoperative CT imaging, and similar post-operative malreduction rates were reported for both the syndesmotic screw and suture button system [16]. In that study, posterior malleolar fractures of ≥25 % were fixed and other fractures were not operated on. However, this practice is outdated and in our clinic all fixable posterior malleolar fractures are treated surgically, which facilitates the anatomic reduction of syndesmosis [21,22].

    View all citing articles on Scopus
    View full text